Angiolipoma is a less common form of lipoma or a benign lump of fatty tissue. An angiolipoma is most commonly found on the forearm. Angiolipomas differ from lipomas in that they have more blood vessels running through them and they are more likely to be painful.
Angiolipomas are relatively common, making up an estimated 5 to 17 percent of all lipomas. Like other lipomas, they are noncancerous. Treatment is not always necessary for angiolipomas, though minor surgery can be used if they need to be removed.
In this article, we take a closer look at angiolipoma, including symptoms, treatment, removal, and its relationship with cancer and other diseases.
Angiolipomas are small, soft lumps found under the skin, usually less than 4 centimeters (cm) wide. They are difficult to differentiate from lipomas by sight unless they contain visible blood vessels.
These lumps usually arise after puberty and are more common in people aged 20 to 30 years old.
Angiolipomas can occur anywhere on the body, but are most common on the:
- upper arms
Less common areas where angiolipomas may appear include the legs, head, face, neck, and hands. In very rare cases, angiolipomas can occur in deeper tissues, where they are called intramuscular hemangiomas.
Spinal angiolipomas can cause pain, difficulty walking, or difficulty urinating. Similarly, gastrointestinal lipomas can cause stomach pain, bleeding, or intestinal obstruction if the angiolipoma is large enough.
Unlike other lipomas, angiolipomas may feel tender or even painful. The skin over the angiolipoma is usually healthy. A person can usually feel it and may notice several other lesions around the area.
Angiolipoma lumps usually have the following symptoms:
- round or spherical in appearance
- soft to touch
- a doughy or rubbery texture when touched
- easily moved
- often occurring in multiples
Some angiolipomas have no known cause. In other cases, they can be caused by:
- Genetics. If a parent or sibling has an angiolipoma, a person is more likely to have them, as well.
- Injury. Angiolipomas can result from blunt trauma, such as a previous car accident.
- Antiretroviral therapies. Medications used to reduce the incidence of viruses, such as HIV, can make angiolipomas more likely.
- Diabetes. A person with diabetes is more likely to develop angiolipomas.
It is not usually necessary to remove angiolipomas unless they are causing significant symptoms or problems for a person. Angiolipomas are usually easy to remove with surgery, though removal can be complicated with growths in deeper tissue, such as the spine.
If surgery is not required, corticosteroid injections can shrink or get rid of an angiolipoma by causing the fat cells to shrink and die. This involves injecting a local anesthetic and steroid mixture into the lipoma. Sometimes, a doctor must administer multiple injections.
Once a doctor removes a lipoma, it rarely returns in the same place.
Doctors cannot usually tell if a person has a lipoma or an angiolipoma through simple physical examination. The presence of pain may indicate an angiolipoma rather than a lipoma.
Angiolipomas contain more blood vessels than lipomas. A doctor will usually need to take a biopsy to identify if blood vessels are present in the tumor.
Angiolipomas are not cancerous, but they may resemble liposarcoma, which is a type of cancer that affects the fatty cells.
If a doctor suspects that a new growth may be cancerous, they may order further tests, such as a biopsy or MRI scan, to look for cancerous tissues.
Liposarcoma is very rare in people under 30. Cancerous lipomas are more likely to occur in areas such as behind the abdominal wall, shoulders, and lower extremities.
Angiolipomas can also be mistaken for other disorders such as Dercum’s disease, which causes multiple painful lumps to appear along with other symptoms, including weight gain, depression, and lethargy. This condition is extremely rare.
Angiolipomas are a form of lipoma. They are slightly firmer than lipomas, contain more blood vessels, and are more likely to be painful. A doctor will take into account a person’s age, medical history, and symptoms when determining if the lump is angiolipoma or something else.
While angiolipomas are more common in 20- to 30-year-olds, lipomas are more common in older adults aged 50 to 70 years old.
Other skin conditions that may be similar to angiolipoma include:
- epidermoid cyst
- rheumatic nodules
- certain skin infections.
Angiolipomas are different from hemangiomas, which are collections of blood vessels.
Hemangiomas are often called ‘strawberry spots,’ because they appear bright red on the surface of the skin. However, hemangiomas do not have fat cells or adipocytes, while angiolipomas do.
Angiolipomas are a benign type of lipoma or tumor that may be tender to the touch but does not usually cause other health complications.
A person may choose to have the angiolipomas surgically removed for cosmetic reasons or to reduce discomfort. If a person is not sure if their bump is an angiolipoma or another type, they should see their doctor.